Hardly a day goes by that one green website or another doesn't showcase a modern, prefabricated, green residence sited either in a bucolic natural environment or carefully slipped into an existing urban neighborhood as infill. There is nothing wrong with these, because, especially using LEED certified strategies, they are built with methods and with materials using less energy during construction and consuming less energy in operation.
Still, it takes significantly more energy to make a new building than it takes to renovate. By reusing as much original material as possible, you can reduce the amount of new material necessary for construction and conserve resources.
New homes are now less expensive because of the bursting of the housing bubble, but money is tight and loans are harder to qualify for. Chances are that a better investment would be to increase the value of your existing property through renovation and environmentally responsible improvements. When housing prices start to go up again, as you know they will, a remodeled green home will have a marketable competitive advantage.
If you're in no hurry to move, check in your community to see what rebates, tax incentives and other incentives may be available. There are existing partnership programs with power companies and municipalities that are worth investigating, such as:
Build San Antonio Green
San Antonio, TX
Green Building Program